This invention relates to external fixation or adjustable bone stabilizing frame systems and, more particularly, to frame assemblies employed with broken and/or fractured bones for retaining and holding the bone and in a desired configuration for resetting.
The use of external fixation or stabilizing frames for retaining broken or fractured bones in a particularly desired orientation or configuration is widely known and commonly employed. However, in most typical prior art external frame constructions, particularly frame constructions employed to stabilize broken or fractured bones, a variety of clamps and holding rods are employed to enable the surgeon to position the broken/fractured bones in a precisely desired position or orientation, and then allowing the bone to be retained in that position or orientation for healing.
Although wide variety of frame structures and clamp systems have been used for this purpose, one common problem existing with most prior art stabilizing frame constructions is the inability to allow the frame construction to be easily adjustable during its assembly. In this regard, in most applications, anchor pins or anchor screws are mounted in a fractured bone, extending outwardly therefrom for attachment to a frame assembly. Clamp members are mounted to the anchor pins or anchor screws with a plurality of rod members being mounted to a plurality of interconnecting clamps to establish the desired stabilizing frame assembly. However, during the creation of the frame structure, which must be maintained in a precise orientation in order to assure that the bone fracture is precisely aligned for healing, these prior art frame systems have been found to be incapable of being retained in a desired position unless securely clamped. As a result, repeated tightening and loosening of the clamps is required before the precisely desired frame structure is fully assembled.
In those instances where the frame assembly being created has an insufficient clamping force applied to the rod members for securing the rod members in the clamp, slippage of the rod in the clamp often occurs. This causes the frame structure to become improperly aligned, resulting in repeated efforts to recreate and readjust the frame.
In addition, since improper alignment may cause the bone elements to be dislodged from the desired position or may impose improper forces upon the bone elements, the slippage caused by loose rods cannot be tolerated. As a result, the arduous task of clamping and unclamping every interconnection must be imposed upon the physician, in order to assure a frame structure is created having the precisely desired configuration and orientation and is maintained in that position throughout its assembly.
In an attempt to satisfy this need, some clamp members incorporate coil springs to prevent slippage. However, these systems do not provide the desired result and are expensive to produce.
Therefore, it is a principal object of the present invention to provide an adjustable frame structure for stabilizing broken or fractured bones which is capable of being the easily constructed by attaching two anchoring pins or screws, with all compounds thereof being retained in any desired position, without the application of final clamping forces.
Another object to the present invention is to provide an adjustable frame structure having the characteristic features described above which allows ease of assembly while still assuring secure, clamped interengagement of all components when required.
Another object of the present invention is to provide an adjustable frame structure having the characteristic features described above which automatically incorporates friction engagement between sliding components for maintaining such component in any position without requiring a clamping force.
Other and more specific objects will impart the obvious and will impart appear hereinafter.
By employing the present invention, all of the difficulties and drawbacks found in the prior art are eliminated and a fully external fixation or adjustable frame structure is provided which is capable of being quickly and easily assembled in any desired configuration. In addition, the frame structure of the present invention is retained in any assembled configuration in order to allow final adjustments to be made, prior to the final securement of the frame assembly in the precisely desired configuration by closure of each clamp member. In this way, an entire frame assembly is capable of being constructed, adjusted, and readjusted in order to assure each component is oriented in the precisely desired position prior to final closure of the clamp being members.
In order to attain this previously unrealized goal, the clamping members employed in the frame structure of the present invention incorporate friction pins internally mounted in each clamp which engages the rod member once this rod is inserted into the jaws of the clamp. In this way, any rod member inserted into the clamping jaws contacts the surface of the jaws and the friction pin. This contact prevents the rod member from sliding or moving relative to the clamp. As a result of this friction engagement, the rod member is retained in any position relative to the clamping jaws, once the rod member has been inserted into the jaws of the clamp.
By employing the present invention, a frame assembly is quickly in easily constructed in the overall desired configuration with every rod member and clamp being retained in the position originally placed. Once the basic frame structure has been created, final adjustments can be easily made by moving the rod members relative to the clamping jaws, with complete assurance that unwanted slippage will not occur. Once the final configuration has been obtained, each clamp is closed to securely engage the jaws of the clamp with the rod member, thereby assuring the creating of an external fixation assembly or frame structure having a precisely desired configuration for imparting the desired beneficial results.
In addition, the external fixation system or frame assembly of the present invention incorporates components capable of being secured to anchor pins or screws having a wide variety of diameters. By incorporating a uniquely constructed, moving wedge plate that is adjustably engageable with any cooperating anchor pin, secure affixation of the mounting member with the anchor pins is easily achieved, regardless of the orientation configuration, or diameter of the anchor pin.
The invention accordingly comprises the features of construction, combination of elements and arrangement of parts which will be exemplified in the constructions hereinafter set forth, and the scope of the invention will be indicated in the claims.